Because of its effectiveness and comparatively low cost, zinc plating has received wide spread commercial application for the corrosion protection of ferrous substrates and also as a decorative finish. Zinc electroplating baths and processes of the types heretofore known have incorporated various brighteners to enhance the brightness of the deposited zinc plate further enhancing the appearance of the plated article. While such prior art compositions and techniques have been effective in producing relatively bright zinc deposits, a continuing problem has been the lack of achieving a desired degree of leveling or smoothness of the deposit. This problem is further aggravated by the fact that such bright zinc deposits are frequently applied on surfaces of articles which are relatively unfinished, rough and uneven thereby further magnifying surface roughness.
The improved non-cyanide zinc electroplating bath composition and process of the present invention provides for a leveling heretofore unattainable with bath compositions and processes previously known, and further provides a smooth, bright and adherent zinc plating deposit of excellent corrosion and aesthetic appearance.